Tissue fixation and repair systems and methods

ABSTRACT

A system and method for securing an implantable medical device to an anatomical feature, such as bony structures and/or soft tissues near the spine. The system includes a tissue fixation device and a tissue fixation device delivery tool. The tissue fixation device includes at least one bone or tissue anchor and a connecting element coupled thereto. The tissue fixation device optionally includes a flexible anchoring strap for engaging the implantable medical device. The bone or tissue anchor are configured to be deployed into the anatomical feature, and the connecting element is tightened to secure the implantable medical device to the anatomical feature.

TECHNICAL FIELD

The present invention relates to medical devices and methods forimplanting implantable medical devices. More specifically, the inventionrelates to devices and methods for securing implantable medical devicesto bony structures and soft tissues of a patient.

BACKGROUND

The implantation of various implantable medical devices requiressecuring the device to the patient's anatomy to prevent, or at leastinhibit, unintended movement and/or migration of the implanted device.Exemplary such implantable medical devices include spinal stimulationleads, which are typically implanted adjacent to the patient's vertebralcolumn and coupled to an implantable stimulator to provide selectivenerve stimulation for pain management and the like. Such leads typicallyinclude a flexible insulative body and a compressible anchoring sleevedisposed about the lead body. In a conventional implantation procedure,sutures or other ligatures manually tied around the anchoring sleeve tosecure the anchoring sleeve, and consequently the lead disposed therein,to soft tissues proximate the patient's spinal column. In theseapplications, the anchoring sleeve operates to delimit compressiveforces on the lead itself imposed by the fixation sutures/ligatures.

SUMMARY

The present invention, in Example 1, is a method of securing animplantable medical device to or adjacent to an anatomical feature in apatient. The method comprises providing a fixation device coupled to adelivery tool, the delivery tool including a needle cannula having adistal tip, the fixation device including at least one anchor member anda flexible suture assembly including an adjustable suture loop coupledto the anchor member. The distal tip of the needle cannula is insertedinto the anatomical feature. The at least one anchor member is ejectedfrom the distal tip of the needle cannula into the anatomical feature.The implantable medical device is inserted within the adjustable sutureloop, and a dimension of the adjustable suture loop is reduced totighten the adjustable suture loop about the implantable medical device.

In Example 2, the method of Example 1 wherein the implantable medicaldevice includes a flexible member and a compressible anchoring sleevedisposed about the flexible member, inserting the implantable medicaldevice within the adjustable suture loop includes positioning theanchoring sleeve within the adjustable suture loop, and reducing thedimension of the adjustable suture loop to tighten the adjustable sutureloop about the implantable medical device includes tightening theadjustable suture loop about the anchoring sleeve.

In Example 3, the method of either of Examples 1 or 2 wherein the atleast one anchor member includes a bone anchor and the anatomicalfeature includes a bony structure.

In Example 4, the method of Example 3 wherein the bony structure is avertebral body, and wherein the implantable medical device is aneurostimulation lead.

In Example 5, the method of either of Examples 3 or 4 wherein thefixation device further includes a soft tissue anchor slidably coupledto the adjustable suture loop, and wherein the anatomical featurefurther includes soft tissue proximate the vertebral body, and whereinthe method further comprises removing the distal tip of the needlecannula from the vertebral body and subsequently inserting the distaltip of the needle cannula into the soft tissue and ejecting the softtissue anchor into the soft tissue prior to reducing the dimension ofthe adjustable suture loop to tighten the adjustable suture loop aboutthe anchoring sleeve.

In Example 6, the present invention is a method of securing animplantable medical device to or adjacent to an anatomical feature in apatient. The method comprises positioning the implantable medical devicein proximity to the anatomical feature. A flexible anchoring strap ispositioned against the implantable medical device such that theimplantable medical device lies between the anatomical feature and atleast a portion of the anchoring strap. The anchoring strap is securedto the anatomical feature using an anchoring element.

In Example 7, the method of Example 6 wherein positioning the flexibleanchoring strap includes wrapping the anchoring strap about theimplantable medical device and causing opposite ends of the anchoringstrap to overlap.

In Example 8, the method of either of Examples 6 or 7 wherein securingthe anchoring strap includes inserting a portion of the anchoringelement through the overlapped ends of the anchoring strap and into theanatomical feature.

In Example 9, the method of any of Examples 6-8 wherein the anchoringelement includes a tissue anchor, a flexible connecting elementconnected to the tissue anchor, and a locking element disposed on theconnecting element, and wherein inserting the portion of the anchoringelement through the overlapped ends of the anchoring strap includesinserting a distal end of a delivery tool through the overlapped ends ofthe anchoring strap and into the anatomical feature, ejecting the tissueanchor from the delivery tool and into the anatomical feature,withdrawing the distal end of the delivery tool from the anatomicalfeature and the overlapped ends of the anchoring strap, and deployingthe locking element against a side of the anchoring strap opposite theanatomical feature so as to tighten the connecting element and securethe anchoring strap to the anatomical feature.

In Example 10, the method of Example 6 wherein positioning the anchoringstrap against the implantable medical device includes positioning afirst end of the anchoring strap against the anatomical feature at afirst location and positioning a second end of the anchoring strapagainst the anatomical feature at a second location, the implantablemedical device being positioned between the first and second locationssuch that the anchoring strap spans across and over the implantablemedical device.

In Example 11, the method of Example 10 wherein securing the anchoringstrap to the anatomical feature includes securing the first end of theanchoring strap to the anatomical feature using a first anchoringelement, and securing the second end of the anchoring strap to theanatomical feature using a second anchoring element.

In Example 12, the method of either of Examples 10 or 11 whereinsecuring the first end of the anchoring strap to the anatomical featureincludes inserting a portion of the first anchoring element through thefirst end of the anchoring strap and into the anatomical feature, andsecuring the second end of the anchoring strap to the anatomical featureincludes inserting a portion of the second anchoring element through thesecond end of the anchoring strap and into the anatomical feature.

In Example 13, the method of any of Examples 10-12 wherein the first andsecond anchoring elements each include a tissue anchor, a flexibleconnecting element connected to the tissue anchor, and a locking elementdisposed on the connecting element, and wherein inserting the portion ofthe first anchoring element through the first end of the anchoring strapincludes inserting a distal end of a first delivery tool through thefirst end of the anchoring strap and into the anatomical feature,ejecting the tissue anchor of the first anchoring element from the firstdelivery tool and into the anatomical feature, withdrawing the distalend of the first delivery tool from the anatomical feature and the firstend of the anchoring strap, and deploying the locking element of thefirst anchoring element against a side of the first end of the anchoringstrap opposite the anatomical feature so as to tighten the connectingelement of the first anchoring element and secure the first end of theanchoring strap to the anatomical feature. Additionally, inserting theportion of the second anchoring element through the second end of theanchoring strap includes inserting a distal end of a second deliverytool through the second end of the anchoring strap and into theanatomical feature, ejecting the tissue anchor of the second anchoringelement from the second delivery tool and into the anatomical feature,withdrawing the distal end of the second delivery tool from theanatomical feature and the second end of the anchoring strap, anddeploying the locking element of the second anchoring element against aside of the second end of the anchoring strap opposite the anatomicalfeature so as to tighten the connecting element of the second anchoringelement and secure the second end of the anchoring strap to theanatomical feature.

In Example 14, the method of Example 6 wherein the anchoring elementincludes first and second tissue anchors and a flexible connectingelement therebetween, and wherein the anchoring strap includes oppositefirst and second ends and the connecting element is coupled to andextends along the anchoring strap between the first and second ends, andwherein the first tissue anchor is positioned in proximity to the firstend and the second tissue anchor is positioned in proximity to thesecond end.

In Example 15, the method of Example 14 wherein the anchoring strap andthe anchoring element are pre-assembled and releasably coupled to adelivery tool prior to deployment, the delivery tool including a needlecannula and an open distal end, wherein prior to deployment the firstand second tissue anchors are positioned serially within the needlecannula and the anchoring strap and at least a portion of the connectingelement is positioned external to the needle cannula.

In Example 16, the method of either of Examples 14 or 15 whereinpositioning the anchoring strap against the implantable medical deviceincludes positioning the first end of the anchoring strap against theanatomical feature at a first location and positioning the second end ofthe anchoring strap against the anatomical feature at a second location,the implantable medical device being positioned between the first andsecond locations such that the anchoring strap spans across and over theimplantable medical device.

In Example 17, the method of either of Examples 15 or 16 whereinpositioning the anchoring strap against the implantable medical deviceand securing the anchoring strap to the anatomical feature includesinserting the open distal end of the delivery tool into the anatomicalfeature at a first location, ejecting the first tissue anchor from theopen distal end and into the anatomical feature, withdrawing the opendistal end of the delivery tool from the anatomical feature, insertingthe open distal end of the delivery tool into the anatomical feature ata second location, the implantable medical device being positionedbetween the first and second locations such that the anchoring strapspans across and over the implantable medical device, ejecting thesecond tissue anchor from the open distal end and into the anatomicalfeature, withdrawing the open distal end of the delivery tool from theanatomical feature, and tightening the connecting element to secure theimplantable medical device between the anatomical feature and theanchoring strap.

In Example 18, the present invention is a method of securing animplantable medical device to or adjacent to an anatomical feature in apatient. The method comprises providing a tissue fixation devicereleasably coupled to a delivery tool, the tissue fixation deviceincluding a flexible, adjustable suture assembly, the delivery toolincluding first and second needle elements each having a tissue-piercingtip. The implantable medical device is positioned in proximity to theanatomical feature. The tissue piercing tips of the first and secondneedle elements are inserted into the anatomical feature proximate theimplantable medical device. A portion of the tissue fixation device isdeployed into the anatomical feature, the tissue-piercing tips of theneedle elements are withdrawn from the anatomical feature, and theadjustable suture assembly is tightened to secure the implantablemedical device to the anatomical feature.

In Example 19, the method of Example 18 wherein the tissue fixationdevice further includes first and second tissue anchors coupled to theflexible, adjustable suture assembly, and wherein the first and secondtissue anchors are coupled to the first and second needle elements,respectively, and wherein deploying the portion of the tissue fixationdevice into the anatomical feature includes deploying the first andsecond tissue anchors and a portion of the adjustable suture assemblyinto the anatomical feature.

In Example 20, the method of either of Examples 18 or 19 wherein theadjustable suture assembly includes a first suture loop coupled to thefirst tissue anchor and a second suture loop coupled to the secondtissue anchor, and wherein tightening the adjustable suture assembly tosecure the implantable medical device to the anatomical feature isperformed with the implantable medical device positioned within thefirst and second suture loops, and wherein tightening the adjustablesuture assembly further includes tightening the first suture loop andtightening the second suture loop.

In Example 21, the method of either of Examples 18 or 19 whereininserting the tissue piercing tips includes inserting the tissuepiercing tip of the first needle element into the anatomical feature ona first side of the implantable medical device, and inserting the secondtissue piercing tip of the second needle element into the anatomicalfeature on a second side of the implantable medical device such that aportion of the suture assembly spans across the implantable medicaldevice. Additionally, tightening the adjustable suture assembly includestightening the suture assembly to secure the implantable medical deviceagainst the anatomical feature.

In Example 22, the method of any of Examples 18-21 wherein the first andsecond needle elements are fixed relative to each other, and whereininserting the first and second tissue piercing tips includessimultaneously inserting the first and second tissue piercing tips intothe anatomical feature.

In Example 23, the method of any of Examples 18-21 wherein the first andsecond needle elements are individually actuatable, and whereininserting the first and second tissue piercing tips and deploying thefirst and second tissue anchors includes first inserting the firsttissue piercing tip into the anatomical feature at the first locationand deploying the first tissue anchor, and subsequently inserting thesecond tissue piercing tip into the anatomical feature at the secondlocation and deploying the second tissue anchor.

In Example 24, the method of Example 18 wherein the first needle elementis a first needle cannula having a first side opening, and wherein thesecond needle element is a second needle cannula having a second sideopening located at a position distal to the first side opening, andwherein the adjustable suture assembly includes a pre-tied loop forforming a locking element disposed about the first and second needlecannulas prior to deployment of the tissue fixation device.

In Example 25, the method of Example 24 wherein the delivery toolfurther includes an exchange mandrel having a pre-shaped distal endportion slidably disposed in the first needle cannula, and whereinproviding the tissue fixation device releasably coupled to the deliverytool includes providing a portion of the adjustable suture assemblydisposed along the first needle cannula and coupled to the distal endportion of the exchange mandrel within the first side opening, andwherein deploying the portion of the tissue fixation device into theanatomical feature includes advancing the distal end portion of theexchange mandrel out the first side opening to the second side openingand engaging the second needle cannula with a passing element on adistal end of the portion of the adjustable suture assembly.

In Example 26, the method of Example 25 wherein withdrawing the tissuepiercing tips includes passing the distal end of the portion of theadjustable needle assembly through the pre-tied loop thereby forming thelocking element.

While multiple embodiments are disclosed, still other embodiments of thepresent invention will become apparent to those skilled in the art fromthe following detailed description, which shows and describesillustrative embodiments of the invention. Accordingly, the drawings anddetailed description are to be regarded as illustrative in nature andnot restrictive.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a perspective illustration of a tissue fixation devicesecured to an implantable device according to one embodiment.

FIGS. 1B and 1C are perspective views of the implantable device of FIG.1A secured to a vertebral body using the tissue fixation device of FIG.1A according to one embodiment of the present invention.

FIGS. 2A and 2B, respectively, are schematic illustrations of the tissuefixation device of FIG. 1A and a delivery tool for delivering thefixation device according to one embodiment of the present invention.

FIGS. 3A and 3B are perspective and end views of an alternative tissuefixation device secured to the implantable device of FIG. 1A accordingto another embodiment of the present invention.

FIGS. 4A and 4B are perspective and end views of an alternative tissuefixation device secured to the implantable device of FIG. 1A accordingto another embodiment of the present invention.

FIGS. 5A and 5B are perspective views of an alternative tissue fixationdevice secured to the implantable device of FIG. 1A according to anotherembodiment of the present invention.

FIG. 6 is a perspective view of a portion of the tissue fixation devicesecured to a fixation device delivery tool according to anotherembodiment of the present invention.

FIG. 7A is a perspective view of an alternative tissue fixation devicesecured to the implantable device of FIG. 1A according to anotherembodiment of the present invention.

FIG. 7B is a schematic view of the tissue fixation device of FIG. 7A.

FIG. 8 is a perspective view of an alternative tissue fixation devicesecured to the implantable device of FIG. 1A according to anotherembodiment of the present invention.

FIGS. 9A and 9B are perspective views of the tissue fixation device ofFIGS. 8A and 8B mounted on an alternative fixation device delivery toolaccording to another embodiment of the present invention.

FIGS. 10A and 10B are perspective views of an alternative tissuefixation device mounted on the fixation device delivery tool of FIGS. 9Aand 9B according to another embodiment of the present invention.

FIGS. 11A and 11B are perspective views of an alternative tissuefixation device mounted on the fixation device delivery tool of FIGS. 9Aand 9B according to another embodiment of the present invention.

FIGS. 12A-12F are schematic views of a portion of an alternative tissuefixation device and delivery tool for use in fixating the implantablemedical device of FIG. 1A according to another embodiment.

While the invention is amenable to various modifications and alternativeforms, specific embodiments have been shown by way of example in thedrawings and are described in detail below. The intention, however, isnot to limit the invention to the particular embodiments described. Onthe contrary, the invention is intended to cover all modifications,equivalents, and alternatives falling within the scope of the inventionas defined by the appended claims.

DETAILED DESCRIPTION

FIG. 1A is a illustration of an implantable medical device, which in theillustrated embodiment is a neurostimulation lead 10 coupled to a tissuefixation device 20 according to one embodiment. As shown in FIG. 1A, theneurostimulation lead 10 has an elongate flexible body 22 and ananchoring sleeve 23 disposed about the body 22. In the illustratedembodiment, the neurostimulation lead 10 can be any conventional orlater-developed neurostimulation lead configured for deliveringtherapeutic stimuli to a patient's central nervous system for painmanagement and other therapies. As will be appreciated to those skilledin the art, such leads 10 are configured to be coupled at one end to animplantable pulse generator (not shown) configured to generate electrictherapy stimuli, and have one or more electrodes at or near the oppositeend which when implanted are positioned proximate a specific nerve ornerves selected to provide a desired response to the deliveredelectrical stimulus. Accordingly, the lead 10 is fixated to tissue nearthe patient's vertebral column using the fixation device 20 to inhibitor prevent unintended migration of the lead 10 after implantation.

In the illustrated embodiment, the anchoring sleeve 23 is radiallycompressible and includes a plurality of circumferential grooves 24longitudinally spaced along the anchoring sleeve 23. As further shown,the fixation device 20 includes a bone anchor 25 and a flexibleconnecting assembly 30 coupled thereto. In the illustrated embodiment,the connecting assembly 30 is formed from a length of suture materialand includes an adjustable loop 35 and a proximal tension line 40 thatcan be manipulated by the clinician for tightening and cinching up theadjustable loop 35 to secure the lead 10 to the patient anatomy. Asshown, the anchoring sleeve 23 is positioned within the adjustable loop35, with the suture material of the adjustable loop 35 positioned withinone of the circumferential grooves 24. In the various embodiments, theanchoring sleeve 23 is slidable along the body 22 of the lead 10 priorto tightening adjustable loop 35. As the adjustable loop 35 is tightenedby the clinician, the anchoring sleeve 23 compresses radially tofrictionally engage the lead body 22. The anchoring sleeve 23 operatesin part to distribute the radial forces imposed by the adjustable loop35, to avoid undue stress on the lead 10.

FIGS. 1B and 1C are perspective illustrations showing the lead 10 in animplanted state fixated proximate a patient's vertebra 50 using thefixation device 20 according to one embodiment. As shown in FIGS. 1B and1C, the lead 10 is secured in place utilizing the spinous process 55 ofthe vertebra 50 as an anchoring structure. In the illustratedembodiment, the bone anchor 25 is implanted into the spinous process 55to anchor the fixation device 20 thereto. The anchoring sleeve 23 of thelead 10 extends through the adjustable loop 35 of the fixation device20, and is thereby secured in place. In the illustrated embodiment, theanchoring sleeve 23 is secured directly against the spinous process 55.In other embodiments, the bone anchor 25 can be embedded into other bonystructures or calcified tissue to secure the fixation device 20, andconsequently the lead 10, thereto.

FIGS. 2A and 2B are, respectively, schematic views of the fixationdevice 20 and a fixation device delivery tool 60 for deploying thefixation device 20. As shown in FIG. 2A, the bone anchor has taperedends 64, 66, an intermediate portion 70 therebetween, and a channel 75extending through the intermediate portion 70. As further shown, theconnecting assembly 30 includes a connecting segment 78 extendingthrough the channel 75 and including a distal locking element 80 and aproximal locking element 82. Additionally, a proximal safety line 84extends proximally from the locking element 82. In the illustratedembodiment, the locking elements 80, 82 are in the form of knots in thesuture material forming the connecting segment 78, the knots positionedon opposite sides of the bone anchor 25 to couple the bone anchor 25 tothe connecting assembly 30.

As further shown, in the illustrated embodiment, the adjustable loop 35is formed by a length of suture material which pierces through thesuture material of the connecting segment 78 between the bone anchor 25and the proximal locking element 82, thereby coupling the adjustableloop 35 to the connecting segment 78 and the safety line 84. As furthershown, the adjustable loop 35 includes an adjustable locking element 88,and the proximal tension line 40 extends proximally from the lockingelement 88. In the illustrated embodiment, the locking element 88 is aknot such as a Roeder or Weston knot that allows for unidirectionalsliding movement of the suture material therethrough such that thedimensions of the adjustable loop 35 can be reduced to tighten the loop35 about the anchoring sleeve 23, but which resists reverse movement andconsequent enlargement of the loop 35. In various other embodiments,other locking element structures can be utilized, e.g., pledgets, crimptubes, and knotless locking elements, to provide the functionalitydescribed above.

In the illustrated embodiment, the bone anchor 25 is in the form of aT-anchor and is configured to be insertable into a bore defined incortical and/or cancellous bone material, wherein the insertion occursgenerally in the direction defined between the tapered ends 64, 66.Thereafter, applying tension on the safety line 84 operates to rotate ortoggle the bone anchor 25 until firm engagement of the bone material isachieved. In this manner, the bone anchor 25 becomes firmly embedded inthe bone, with the connecting segment 78 extending through the boreexternal to the bone. Thereafter, tension applied to the tension line 40is resisted by the engagement of the bone anchor 25 and the bone, whichoperates to tighten the adjustable loop 35 about any structure, e.g.,the anchoring sleeve 23 of the lead 10, extending through the loop 35.

As shown in FIG. 2B, the fixation device delivery tool 60, with thefixation device 20 coupled thereto, can be substantially similar oridentical to the fixation delivery apparatus 2010 described inco-pending and commonly assigned U.S. patent application Ser. No.12/552,583 filed Sep. 3, 2009, which is incorporated herein byreference. In the illustrated embodiment, the fixation device deliverytool 60 includes a tubular cannula 100 and a proximal handle 105 coupledthereto. In the illustrated embodiment, the cannula 100 terminates in arelatively blunt distal tip 110. Although not illustrated in FIG. 2B,the fixation device delivery tool 60 further includes an actuatingmechanism in the handle 105 coupled to an ejection rod slidably disposedin the tubular cannula 100. Additionally, the fixation device 20 isreleasably coupled to the fixation device delivery tool 60 with aportion of the connecting assembly 30, including the proximal tensionline 40 and the safety line 84 extending external to the cannula and thebone anchor 25 (not shown in FIG. 2B) disposed within the cannula nearthe distal tip 110, As further shown, the safety line 84 and the tensionline 40 are connected, respectively, to releasable tabs 115 and 118releasably coupled to the handle 105. The tabs 115, 118 allow fortactile manipulation by the clinician to toggle the bone anchor 25within the bony structure and to apply tension to the tension line 40 totighten the adjustable loop 35 as described above.

In use, the bone anchor 25 can be deployed into the spinous process 55(see FIGS. 1B-1C) according to the techniques described in theaforementioned U.S. patent application Ser. No. 12/552,583. For example,a bone awl or similar tool can be used to form a bore into the surfaceof the spinous process 55, and the distal tip 110 of the fixation devicedelivery tool 60 is then inserted into this bore to a desired depth.Next, the bone anchor 25 is ejected from the cannula 105 of the deliverytool 60 and into the bone of the spinous process 55. Once placed intothe bone, the clinician can pull on the tab 115 to apply tension to thesafety line 84 to toggle the bone anchor 25 until it has firmly engagedthe bone. Next, the lead 10 is advance through the adjustable loop 35 ofthe connecting assembly 30, with the anchoring sleeve 23 positionedwithin the loop 35. Once the lead 10 is located in the desired position,the clinician pulls on the tension line 40 (by grasping the tab 118) totighten the loop 35 about the anchoring sleeve 23. Thereafter, anyexcess lengths of the safety line 84 and the tension line 40 can be cutaway using, for example, a scalpel, scissors, a suture cutter, and thelike.

Alternatively, the tissue fixation device 20 can be deployed using, forexample, the implant delivery tool illustrated in FIGS. 9A-9C ofcommonly assigned U.S. patent application Ser. No. 12/853,897, thedisclosure of which is incorporated herein by reference in its entirety.Use of this implant delivery tool obviates the need to separately form abore in the spinous process 55 or other bony structure, as the implantdelivery tool is configured to penetrate the bone during deployment ofthe bone anchor 25.

FIGS. 3A and 3B are perspective and end views of an alternative tissuefixation device 200 securing the neurostimulation lead 10 to soft tissue202 near the patient's spine according to another embodiment of thepresent invention. As shown in FIGS. 3A and 3B, the tissue fixationdevice 200 includes an anchoring strap 205 and an anchor band 210. Asfurther shown, the anchor band 210 includes a tissue anchor 215, aconnecting element 220 and a locking element 225. The tissue anchor 215is in the form of a T-anchor configured to be embedded and retainedwithin the soft tissue 202, e.g., muscle, fascial or connective tissuesuch as the supraspinous ligament. As shown, the connecting element 220is connected to the tissue anchor 215, and the locking element 225 isconnected to the connecting element 220. In various embodiments, theanchor band 210 can be substantially the same or identical to any of thefixation elements (e.g., the fixation elements or anchor bands 308)disclosed in commonly-assigned U.S. patent application Ser. No.11/120,750, the disclosure of which is incorporated herein by referencein its entirety. As such, the locking element 225 is configured to beslidable along the connecting element 220 in a direction toward thetissue anchor 215, but is configured to resist sliding in a reversedirection so as to retain the tissue anchor 215 and the connectingelement 220 under tension when implanted. In various embodiments, thetissue anchor 215 is in the form of a T-anchor or barb, and the lockingelement 225 is a pledget, knot or similar structure configured to allowincreased tension to be applied to the connecting element 220 but toresist reverse movement and subsequent relaxation of this tension. Invarious embodiments, the anchor band 210 can be deployed using any ofthe fixation element or anchor band delivery tools (ABDTs) taught in theaforementioned U.S. patent application Ser. No. 11/120,750.

In the illustrated embodiment, in its implanted state, the strap 205extends circumferentially around the anchoring sleeve 23 of the lead 10such that the ends of the strap 205 double over each other. As furthershown, the connecting segment 220 extends through the doubled-over endportions of the strap 205, with the tissue anchor firmly embedded in thesoft tissue 202 and the locking element 225 bearing against the outersurface of the strap 205 so as to maintain the tissue anchor 215 and theconnecting element 220 under tension. Accordingly, as shown, the anchorband 210 also operates to secure the strap 205, and consequently thelead 10, to the soft tissue 202.

In use, the strap 205 can be positioned either before or after the lead10 itself is positioned according to the preference of the implantingclinician. Either way, the anchoring sleeve 23 is positioned over theportion of the strap 205 adjacent to the soft tissue 202, and the strap205 is then wrapped circumferentially around the anchoring sleeve 23.The anchor band 210 is then deployed to secure the strap 205 and thelead 10 in place. In one embodiment, the anchor band is deployed using adelivery tool (not shown) such as the anchor band delivery tool 400disclosed in the aforementioned U.S. patent application Ser. No.11/120,750. In such an embodiment, the sharpened distal tip of thedelivery tool is inserted through the doubled over end portions of thestrap 205 and into the soft tissue 202 to a desired depth. The tissueanchor 215 is then ejected from the tip of the delivery tool and into orthrough the soft tissue 202. The delivery tool is then actuated to applytension to the anchor band 210 and lock the anchor band 210 undertension using the locking element 225, in the manner described in theaforementioned U.S. patent application Ser. No. 11/120,750. Any excessmaterial of the anchor band 210 (e.g., excess suture material) can thenbe cut away.

In various embodiments, the strap 205 can be formed by any flexiblebiocompatible material. In various embodiments, the strap 205 is formedof a mesh material. In various embodiments, the strap 205 is alsoelastic such that it can be stretched as it is wrapped around theanchoring sleeve 23 and thereafter secured under tension to apply acompressive radial force on the anchoring sleeve 23 to enhance fixationof the anchoring sleeve 23 and lead 10 to the soft tissue 202. Invarious embodiments, the strap 205 includes internal features, e.g.,ribs or projections, configured to be complementary to thecircumferential grooves on the anchoring sleeves 23. That is, whenpresent, these internal features can engage the features of thecircumferential grooves on the anchoring sleeve 23 to inhibit relativeaxial movement of the anchoring sleeve 23 relative to the strap 205. Invarious embodiments, the strap 205 can be made of or include materialsto encourage or inhibit fibrosus or other tissue in-growth.

FIGS. 4A and 4B are perspective and end views of an alternative tissuefixation device 250 securing the neurostimulation lead 10 to soft tissue202 near the patient's spine according to another embodiment of thepresent invention. As shown in FIGS. 4A and 4B, the tissue fixationdevice 250 includes an anchoring strap 255 and a pair of anchor bands256, 258. As further shown, the anchor band 256 includes a tissue anchor260, a connecting element 262 and a locking element 265. Similarly, theanchor band 258 includes a tissue anchor 270, a connecting element 272and a locking element 275. The strap 255 and each of the anchor bands256, 258 can, except as described below, be substantially the same as oridentical to the anchoring strap 205 and the anchor band 210 describedin connection with the embodiment of FIGS. 3A-3B, except that in theembodiment of FIGS. 4A and 4B the anchoring strap 255 does not wrapsubstantially completely around the anchoring sleeve 23 and double overon itself. Rather, as shown in FIGS. 4A-4B, the anchoring strap 255 isdisposed over the anchoring sleeve 23 of the lead 10 and attached to thesoft tissue 202 at opposite ends of the anchoring strap 255 by therespective anchor bands 256, 258. The anchor bands 256, 258 can bedeployed and tightened in the same manner described above with respectto the anchor band 215, and consequently, as the fixation elements oranchor bands (e.g., the fixation element/anchor band 308) disclosed inthe aforementioned U.S. patent application Ser. No. 11/120,750.

FIGS. 5A-5C are perspective and end views of an alternative tissuefixation device 300 securing the neurostimulation lead 10 to soft tissue202 near the patient's vertebra 50 according to another embodiment ofthe present invention. As shown in FIGS. 5A-5C, the tissue fixationdevice 300 includes an anchoring strap 305 and an adjustable tensionband 310 coupled to the anchoring strap 305. As further shown, theadjustable tension band 310 includes a pair of tissue anchors 315, 318and an adjustable connecting assembly 320 between the tissue anchors315, 318. As further shown, the adjustable connecting assembly 320 iswoven or otherwise extended through and along the anchoring strap 305 tocouple these structures together.

In various embodiments, the adjustable tension band 310 and itscomponents are configured to be substantially the same as or identicalto any of the fixation devices disclosed in co-pending and commonlyassigned U.S. patent application Ser. No. 11/120,750, or the implantsillustrated in FIGS. 5A-5C and 6A-6C of co-pending and commonly assignedU.S. patent application Ser. No. 12/853,897. Accordingly, each of theaforementioned patent applications is incorporated herein by referencefor all purposes. Thus, in the various embodiments, the adjustabletension band 310 is configured such that the tissue anchors 315, 318 canbe deployed into and embedded within the soft tissue 202 and the lengthof the adjustable connecting assembly 320 can be reduced between thetissue anchors 315, 318, thereby tightening the connecting assembly 320and securing the anchoring strap 305, and the anchoring sleeve 23 of thelead 10, to the soft tissue 202. In various embodiments, the anchoringstrap 305 can be substantially similar or identical to the anchoringstraps 205 or 255 discussed above.

FIG. 6 is a perspective view of a portion of the tissue fixation device300 loaded onto a fixation device delivery tool 350 prior to deploymentaccording to one embodiment of the present invention. As shown in FIG.6, the fixation device delivery tool 350 includes a tubular needlecannula 355 having an open distal end 360 terminating in a sharptissue-penetrating tip 365. As further shown, the assembled tissuefixation device 300 is coupled to the needle cannula 355 with the tissueanchors 315, 318 disposed within the needle cannula 355 and theanchoring strap 305 positioned external to the needle cannula 355.Additionally, a portion of the connecting assembly 320 extends through aslot 368 in the needle cannula 355, with a tension line 370 of theconnecting assembly 320 extending toward the proximal end of thefixation device delivery tool 350 so that it can be manipulated by aclinician to tighten the connecting assembly 320 as described above.

In various embodiments, the fixation device delivery tool 350 can besubstantially similar or identical to, for example, the implant deliverytools illustrated in FIGS. 1 and 7 of the aforementioned U.S. patentapplication Ser. No. 12/853,897, which is incorporated herein byreference in its entirety, or comparable devices. As such, the fixationdevice delivery tool 350 includes an actuator mechanism that allows forserial deployment of the tissue anchors 315, 318 into the soft tissue202, and also for adjusting the adjustable length of the connectingassembly 320 between the tissue anchors 315, 318.

Thus, in use, the lead 10 and the anchoring sleeve 23 (see FIGS. 5A-5C)are positioned as desired, and the tip 365 of the needle cannula 355 isinserted into the soft tissue 202 a desired depth at a locationproximate the anchoring sleeve 23. The tissue anchor 315 is then ejectedthrough the open distal end 360 of the needle cannula 355, e.g., byadvancing an ejection rod (not shown) disposed within the needle cannula355 using the above mentioned actuator mechanism. The distal tip 365 isthen removed from the soft tissue 202, relocated to a position on theopposite side of the anchoring sleeve 23 with the anchoring strap 305disposed over the anchoring sleeve 23, and re-inserted into the softtissue 202. The tissue anchor 318 is then deployed into the soft tissue202 by advancing the above mentioned ejection rod a second distance. Inthis regard, the tension band 310 is deployed in substantially the samemanner as described in the above mentioned U.S. patent application Ser.No. 12/853,897, except that rather than extending the connectingassembly 320 across a defect in an annulus fibrosus of the disc, theconnecting assembly 320 is extended across the anchoring sleeve 23 ofthe lead 10. Thereafter, the tension line 370 can be pulled so as totighten the connecting assembly 320 between the tissue anchors 315, 318and secure the anchoring sleeve 23, and consequently the lead 10, to thesoft tissue 202.

FIG. 7A is a perspective view of an alternative tissue fixation device400 secured to the implantable neurostimulation lead 10 according toanother embodiment of the present invention, and FIG. 7B is a schematicview of the tissue fixation device 400 with the lead 10 not shown. Asshown in FIGS. 7A-7B, the tissue fixation device 400 includes a boneanchor 405, a tissue anchor 410, and an adjustable connecting assembly415 connecting the bone anchor 405 and the tissue anchor 410. As furthershown, the connecting assembly 415 forms an adjustable loop 420 throughwhich the anchoring sleeve 23 is disposed, and further includes anadjustable locking element 425 to facilitate unidirectional adjustment(i.e., tightening) of the adjustable loop 420. In various embodiments,the locking element 425 can be a knot (e.g., a Roeder knot, a Westonknot, or the like), a mechanical element (e.g., a pledget or comparablestructure), or can be in the form of a knotless suture lockingarrangement such as the knotless locking elements of the implantsillustrated in FIGS. 5A-5C and 6A-6C of co-pending and commonly assignedU.S. patent application Ser. No. 12/853,897, the disclosure of which isincorporated herein by reference.

In various embodiments, the tissue fixation device 400 is in manyrespects similar or identical to the tissue fixation device 20 describedabove, with the addition of the tissue anchor 410. Thus, as shown, thebone anchor 405 is fixedly secured to the connecting assembly 415 via aconnecting segment 426, and a safety line 427 extends proximally fromthe connecting segment 426 in the manner described above with respect tothe safety line 84 of the tissue fixation device 20. Additionally, atension line 428 extends from the locking element 425 and is operable toallow the clinician to tighten the adjustable loop 420. In theillustrated embodiment, the tissue anchor 410 is slidably connected tothe connecting assembly 415 via a suture loop 429 disposed about thesuture material forming the adjustable loop 420. Thus, as the adjustableloop 420 is tightened, the tissue anchor 410 can slide along the loop420.

In the illustrated embodiment, the tissue fixation device 400 isconfigured to secure the neurostimulation lead 10 to both bonystructures (e.g., the vertebrae) and adjacent soft tissues such asmuscle, fascia, or connective tissue. The tissue fixation device 400 maybe deployed using, for example, the fixation device delivery tool 350described above, in which case the bone anchor 405 and the tissue anchor410 would be positioned serially within the needle cannula 355 prior todeployment. In one embodiment, the bone anchor 405 is positioned distalto the tissue anchor 410 within the needle cannula 355, whereas in otherembodiments the tissue anchor 410 would be distal to the bone anchor405. In another embodiment, the tissue fixation device 400 can bedeployed using the implant delivery tool illustrated in FIGS. 9A-9C ofcommonly assigned U.S. patent application Ser. No. 12/853,897, which isincorporated herein by reference. In such embodiments, the tissue anchor410 would be positioned proximal to the bone anchor 405 within thedelivery tool cannula, which has the capability of forming the bore intothe vertebra or other bony structure itself without a separate boringstep. Thus, in this embodiment, the bone anchor 405 is deployed firstand the tissue anchor 410 second.

In use, either the bone anchor 405 or the tissue anchor 410 is deployedinto the respective anatomical feature first, depending on theparticular delivery tool utilized. The lead 10 can then be advancedthrough the loop 420 so that the anchoring sleeve 23 is positionedtherein, and the tension line 428 is then pulled to tighten theadjustable loop 420 about the anchoring sleeve 23. Any excess lengths ofthe connecting assembly 415 are then cut and removed.

FIG. 8 is a perspective views of an alternative tissue fixation device500 secured to the implantable neurostimulation lead 10 according toanother embodiment of the present invention. As shown in FIG. 8, thetissue fixation device 500 includes a pair of tissue anchors 505, 508and a flexible connecting assembly 510 therebetween. As further shown,the tissue anchors 505, 508 are configured to be embedded and anchoredwithin soft tissue 202, e.g., muscle, fascial, or connective tissue,proximate the patient's spine. Additionally, the flexible connectingassembly 510 connects the tissue anchors 505, 508 and includes a lockingelement 517, which in the illustrated embodiment is a knotless suturelocking arrangement in which a length of suture extends within thetubular wall of the suture material forming the connecting assembly 510.Thus, the connecting assembly 510 can be tightened, e.g., by applyingtension to a tension line 515 after deploying the tissue anchors 505,508, to cinch and secure the anchoring sleeve 23 of the lead 10 againstthe soft tissue 202 in the manner similar to the techniques describedabove. In various embodiments, the tissue fixation device 500 can beconfigured to be similar or identical to the implants illustrated inFIGS. 5A-5C and 6A-6C of co-pending and commonly assigned U.S. patentapplication Ser. No. 12/853,897. Thus, in one embodiment, the tissueanchor 505 can be deployed into the soft tissue 202, the connectingassembly 510 can be extended across the anchoring sleeve 23, and thetissue anchor 508 can then be deployed into the soft tissue 202. Then,the tension line 515 can be pulled to shorten the connecting assembly510 and secure the anchoring sleeve 23, and consequently the lead 10,against the soft tissue 202. Any excess lengths of the tension line 515or other aspects of the connecting assembly 510 can then be cut away andremoved.

FIGS. 9A and 9B are perspective views of the tissue fixation device 500mounted on an alternative fixation device delivery tool 550 according toanother embodiment of the present invention. As shown in FIGS. 9A and9B, the fixation device delivery tool 550 includes a handle 555 and abifurcated needle cannula 557 having a pair of pointed distal endportions 558, 560. As shown, the distal end portions 558, 560 include,respectively, open distal ends 561, 562 and sharpened distal tips 563,564. Additionally, the fixation device delivery tool 550 furtherincludes a plunger 570 and a releasable tab 575 is coupled the plunger570 proximal to the handle 555. In the illustrated embodiment, thetissue fixation device 500 is releasably mounted to the distal endportions 558, 560, with the tissue anchors 505, 508 disposed therein. Asfurther shown, the tension line 515 of the connecting assembly 510extends proximally external to the delivery tool 550 and is connected tothe tab 575.

Although not visible in FIGS. 9A and 9B, the plunger 570 is connected toa bifurcated ejection rod having a segment extending within each of thedistal end portions 558, 560, and the plunger 570 includes a knob 577that can be manipulated by the clinician to actuate the plunger 570.Additionally, the plunger 570 is movable longitudinally relative to thehandle 555 such that the ejection rod can be extended distally to ejectthe tissue anchors 505, 508 from the open distal ends 561, 562 of thecannula distal end portions 558, 560. Additionally, as shown, the tab575 is positioned between the plunger knob 577 and the handle 555 toprevent spontaneous movement of the plunger 570 and ejection of thetissue anchors 505, 508. To operate the plunger 570, the tab 575 isremoved such that the plunger 570 can be pushed toward the handle 555.

The distal end portions 558, 560 are selectively spaced to allow theanchoring sleeve 23 (shown in phantom in FIG. 9B) to fit therebetween.Thus, in use, the lead 10 and anchoring sleeve 23 are positioned asdesired against the soft tissue to which it will be secured, and thedistal end portions 558, 560 are simultaneously inserted into the softtissue on opposite sides of the anchoring sleeve 23 and the connectingassembly 510 spanning over the anchoring sleeve. The tab 575 is thenremoved from the plunger 570, which is then pushed distally to deploythe tissue anchors 505, 508 into the soft tissue. The tab 575 is thenmanipulated by the clinician to pull on the tension line 515, whichshortens the connecting assembly 510 between the tissue anchors 505, 508and tightens or cinches the anchoring sleeve against the soft tissue.

FIGS. 10A and 10B are perspective views of an alternative tissuefixation device 600 mounted on the fixation device delivery tool 550according to another embodiment of the present invention. As shown inFIGS. 10A and 10B, the tissue fixation device 600 is in many respectssimilar to or identical to the tissue fixation device 500, and includesa pair of tissue anchors 605, 608 each releasably disposed in the distalend portions 558, 560 of the delivery tool 550, and a flexibleconnecting assembly 610 connecting the tissue anchors 605, 608.Additionally, the connecting assembly 610 includes a tension line 615extending and connected to the tab 575 releasably coupled to the plunger570. The tissue fixation device 600 differs from the tissue fixationdevice 500 primarily in that the connecting element 610 includes a knot(e.g., a Roeder knot, Weston knot, or the like) as a locking element617, as compared to the knotless locking element 517 utilized in thetissue fixation device 500. The tissue fixation device 600 is otherwisesimilar or identical to the tissue fixation device 500, and can bedeployed in the same or similar manner to secure the lead 10 to softtissue.

FIGS. 11A and 11B are perspective views of an alternative tissuefixation device 700 mounted on the fixation device delivery tool 550according to another embodiment of the present invention. As shown inFIGS. 11A and 11B, the tissue fixation device 700 includes a pair oftissue anchors pair of tissue anchors 705, 708 releasably disposed,respectively, in the distal end portions 558, 560 of the delivery tool550. As further shown, an adjustable suture loop 712 including a lockingelement 713 and a tension line 714 extending therefrom is connected tothe tissue anchor 705, and an adjustable suture loop 716 including alocking element 717 and a tension line 718 extending therefrom isconnected to the tissue anchor 708. Additionally, the tension lines 714,718 are each connected to the releasable tab 575. When used inconnection with the tissue fixation device 700 the delivery tool 550operates in substantially or identically the same manner as describedabove. In particular, the plunger 570 can be pushed distally tosimultaneously eject the tissue anchors 705, 708 into soft tissue towhich the lead 10 or other implantable device will be anchored.Additionally, the tab 575 can be manipulated by the clinician to applytension to the tension lines 714, 718 to reduce the dimensions of theadjustable loops 712, 716. In the illustrated embodiment, the lockingelements 713, 717 are in the form of sliding knots, e.g., Roeder,Weston, or the like, which allow unidirectional adjustment of the sutureloop dimensions.

In use, the tissue anchors 705, 708 are simultaneously deployed into thesoft tissue (e.g, muscle, fascial, or connective tissues) at the desiredimplantation site, and the lead 10 is positioned with the anchoringsleeve 23 (not shown in FIGS. 11A and 11B) disposed within the interiorof the suture loops 712, 716. The tab 575 can then be manipulated tosimultaneously apply tension to both tension lines 714, 718 to tightenthe adjustable suture loops 712, 716 about the lead anchoring sleeve andsecure the lead in place. The tissue fixation device 700 thusadvantageously allows the clinician to secure the anchoring sleeve 23,and consequently the lead 10, in place using two separate suture loopsat the same time. In other embodiments, however, each tension line 714,718 can be connected to a separate tabs to allow for separate, selectivetightening of each of the suture loops 714, 718.

In various embodiments, alternative tissue fixation devices can be usedwith and deployed using the tissue fixation device delivery tool 550. Invarious embodiments, tissue fixation devices utilizing anchoring patchesor straps can be utilized. In one embodiment, the tissue fixation device300 described above can be releasably mounted on and deployed using thedelivery tool 550.

In addition, in the illustrated embodiment, the fixation device deliverytool 550 includes fixed distal end portions of the needle cannula 557,thus in effect providing fixed, dual-needles for simultaneouslydeploying two tissue anchors, in various other embodiments, the fixationdevice delivery tool 550 can instead include a pair of independentneedle cannulas that can be advanced independently of one another. Forexample, in one embodiment, the fixation device delivery tool 550 caninclude a pair of needle cannulas with a respective tissue anchorcoupled thereto within and near the open distal end, with each needlecannula slidably disposed within an outer tube or sheath and coupled toan actuator mechanism in the handle of the tool 550. In this embodiment,the actuator mechanism can be configured to advance a first one of theneedle cannulas independently of the other, to deploy the tissue anchormounted on or within the advanced needle cannula, to withdraw thisneedle cannula from the tissue after deployment of the first tissueanchor, and then to advance the other needle cannula into the tissue andsubsequently deploy the second tissue anchor.

In one embodiment, in lieu of a pair of needle cannulas, the tissuefixation delivery tool can utilize a pair of solid or substantiallysolid needles, and the tissue anchors are releasably coupled to theexteriors of the respective needle distal ends by way of hooks or otherretaining features formed in or provided on the needles. In oneembodiment, the retaining feature(s) can be configured to automaticallyrelease or disengage the respective tissue anchor upon retraction of theneedle from the tissue.

FIGS. 12A-12F are schematic views of a portion of an alternative tissuefixation device 800 and tissue fixation device delivery tool 805according to another embodiment. As shown, the tissue fixation device800 takes on the form of a suture loop with a pre-tied locking element810, e.g., a knot such as a Weston knot, enabling the tissue fixationdevice 800 to secure an implantable medical device such as theneurostimulation lead 10 to soft tissue as illustrated in FIG. 12A. Asfurther shown, the tissue fixation device delivery tool 805 includesdual needle cannulas 812, 814 each capable of penetrating the softtissue 202 to which the lead 10 is to be secured. As further shown, theneedle cannula 812 includes a side opening 818 facing the needle cannula814, and the needle cannula 814 has a side opening 820 facing the needlecannula 812 and located distal to the side opening 818. Additionally,the tissue fixation device delivery tool 805 includes an exchangemandrel 825 slidable within the needle cannula 812 and including aneedle tip element 830, which in its pre-deployed state is piercedthrough the suture material of the tissue fixation device 800 (see FIG.12D). As shown, for example, in FIG. 12B, the locking element 810 isinitially formed as a suture loop disposed about the needle cannulas812, 814 prior to deployment. Additionally, the suture material of thetissue fixation device 800 extends along the exterior of the needlecannula 812, and the exchange mandrel 825 extends within the needlecannula 812 with the needle tip element 830 coupled to the suturematerial proximate and within the side opening 818.

The tissue fixation device delivery tool 805 is configured to form thetissue fixation device 800 in situ by causing the exchange mandrel 825,the needle tip element 830, and the distal end of the suture coupledthereto to pass from the needle cannula 812 through the side opening 820and into the interior of the needle cannula 814, as shown in FIG. 12C.In the various embodiments, the exchange mandrel 825 has a pre-shapeddistal end portion configured to direct the needle tip element 830, andconsequently, the distal end of the suture material coupled thereto, outof the side opening 818 and into the side opening 820. Additionally, thedistal end of the suture material includes or is formed into apre-shaped passing element 835 configured to engage the needle cannula814 within or proximate the side opening 820 (see FIGS. 12C-12D). Asshown in FIG. 12E, the exchange mandrel 825 can then be retractedproximally so as to withdraw the needle tip element 830 from the needlecannula 814, whereby the needle tip element 830 is released fromengagement with the distal end of the suture material due to thepositive engagement of the passing element 835 with the needle cannula814. The needle cannulas 812, 814 can thereafter be retracted from thetissue 202, whereby the distal end of the suture, including the passingelement 835, is routed through the pre-tied locking element 810, whichitself slides along and is eventually released from the needle cannulas812, 814 as shown in FIG. 12F. The resulting structure thus forms thesuture loop of the tissue fixation device 800.

Thus, in use, the needle cannulas 812, 814 are inserted into the softtissue of the implantation site, with the anchoring sleeve 23 of thelead 10 positioned between the needle cannuals 812, 814 and also betweenthe suture of the fixation device 800 and the needle cannula 814 (seeFIG. 12B). The exchange mandrel 825 is then advanced distally within theneedle cannula 812. In one embodiment, the needle tip element 830 ispierced through the distal end of the suture material of the fixationdevice 800 during assembly of the fixation device 800 to the deliverytool 805 (see FIG. 12D). In one embodiment, the needle tip element 830pierces through and engages the suture material as the exchange mandrelis advanced distally within the needle cannula 812.

As shown, the exchange mandrel 825 is further advanced distally so thatthe needle tip element 830 exits the needle cannula 812 through the sideopening 818, with the pre-shaped configuration of the distal end portionof the exchange mandrel 825 directing the needle tip element 830 and thedistal end of the suture into the side opening 820 of the needle cannula814. (FIGS. 12C-12D). As discussed above, the shape of the passingelement 835 engages the needle cannula 814 thereby also coupling thesuture material thereto so that the needle tip element 830 can bedisengaged from the suture and retracted proximally within the needlecannula 812 leaving the suture engaged with the needle cannula 814.(FIG. 12E).

As shown in FIG. 12F, the needle cannulas 812, 814 are then withdrawnfrom the tissue 202. As further shown, this causes the distal end of thesuture to be drawn through the loop forming the pre-tied locking element810 (e.g., a Weston or similar knot). Additionally, because the suturematerial is also routed through the tissue 202, the locking element 810slides over the needle cannulas 812, 814 and is eventually releasedcompletely therefrom, as shown in FIG. 12F. The resulting constructforms the suture loop of the fixation device 800 extending within thesoft tissue 202 and over the anchoring sleeve 23 and including theadjustable Weston knot as the locking element 810. The tissue fixationdevice 800 is then tightened to secure the anchoring sleeve 23 to thesoft tissue and secure the lead 10 in place. Excess lengths of suturematerial can then be cut and removed using any suitable means. Thetissue fixation device 800 and delivery tool 805 thus provide a quickand efficient means for securing the lead 10 in lieu of manually tying asuture loop.

In various embodiments, the exchange mandrel 825 can be made from ahighly flexible and elastic material to allow it to navigate through theneedle cannula 812 and into the needle cannula 814. In one embodiment,the exchange mandrel 825 is made of superelastic materials such asnitinol, which also exhibits shape memory so as to retain the pre-formedshape necessary to ensure that it will pass effectively from one needlecannula 812 to the other needle cannula 814. In one embodiment, theexchange mandrel 825 is formed from spring steel or anotherbiocompatible material having comparable strength and flexibility.

In general, the materials used in the various tissue fixation devicesand delivery tools described herein can include any number ofbiocompatible materials having suitable mechanical properties. Materialsof which to make the cannulas of the tissue fixation device deliverytools and also the bone and tissue anchors of the tissue fixationdevices can include, but are not limited to: metals, such as stainlesssteel, nickel, titanium alloy, and titanium; plastics, such aspolytetrafluoroethylene (PTFE), polypropylene, polyether etherketone(PEEK™), polyethylene, polyethylene teraphthalate (PET) andpolyurethane, acrylic, polycarbonate, engineering plastics; and/orcomposites. The adjustable connecting elements, anchor bands and tensionbands of the various tissue fixation devices can likewise be made of anysuitable suture material. In various embodiments, these elements aremade wholly or partially of size 2-0 or 3-0 force fiber suture material.In short, any suitable materials, whether now known or later developed,can be utilized to construct the various tissue fixation devices anddelivery tools described herein, within the scope of the presentinvention.

Although the various embodiments of the tissue fixation devices andassociate delivery tools described herein have been described for use inanchoring implantable neurostimulation leads to bone or tissue, it isemphasized that the devices and methods described herein are readilyutilized in securing other implantable devices to the patient anatomy.Exemplary other devices include, for example, other types of implantablestimulation leads or electrodes, catheters, and the like.

Various modifications and additions can be made to the exemplaryembodiments discussed without departing from the scope of the presentinvention. For example, while the embodiments described above refer toparticular features, the scope of this invention also includesembodiments having different combinations of features and embodimentsthat do not include all of the described features. Accordingly, thescope of the present invention is intended to embrace all suchalternatives, modifications, and variations as fall within the scope ofthe claims, together with all equivalents thereof.

1. A method of securing an implantable medical device to or adjacent toan anatomical feature in a patient, the method comprising: providing afixation device coupled to a delivery tool, the delivery tool includinga needle cannula having a distal tip, the fixation device including atleast one anchor member and a flexible suture assembly including anadjustable suture loop coupled to the anchor member; inserting thedistal tip of the needle cannula into the anatomical feature; ejectingthe at least one anchor member from the distal tip of the needle cannulainto the anatomical feature; inserting the implantable medical devicewithin the adjustable suture loop; and reducing a dimension of theadjustable suture loop to tighten the adjustable suture loop about theimplantable medical device.
 2. The method of claim 1 wherein: theimplantable medical device includes a flexible member and a compressibleanchoring sleeve disposed about the flexible member; inserting theimplantable medical device within the adjustable suture loop includespositioning the anchoring sleeve within the adjustable suture loop; andreducing the dimension of the adjustable suture loop to tighten theadjustable suture loop about the implantable medical device includestightening the adjustable suture loop about the anchoring sleeve.
 3. Themethod of claim 2 wherein the at least one anchor member includes a boneanchor and the anatomical feature includes a bony structure.
 4. Themethod of claim 3 wherein the bony structure is a vertebral body, andwherein the implantable medical device is a neurostimulation lead. 5.The method of claim 4 wherein the fixation device further includes asoft tissue anchor slidably coupled to the adjustable suture loop, andwherein the anatomical feature further includes soft tissue proximatethe vertebral body, and wherein the method further comprises removingthe distal tip of the needle cannula from the vertebral body andsubsequently inserting the distal tip of the needle cannula into thesoft tissue and ejecting the soft tissue anchor into the soft tissueprior to reducing the dimension of the adjustable suture loop to tightenthe adjustable suture loop about the anchoring sleeve.
 6. A method ofsecuring an implantable medical device to or adjacent to an anatomicalfeature in a patient, the method comprising: positioning the implantablemedical device in proximity to the anatomical feature; positioning aflexible anchoring strap against the implantable medical device suchthat the implantable medical device lies between the anatomical featureand at least a portion of the anchoring strap; and securing theanchoring strap to the anatomical feature using an anchoring element. 7.The method of claim 6 wherein positioning the flexible anchoring strapincludes wrapping the anchoring strap about the implantable medicaldevice and causing opposite ends of the anchoring strap to overlap. 8.The method of claim 7 wherein securing the anchoring strap includesinserting a portion of the anchoring element through the overlapped endsof the anchoring strap and into the anatomical feature.
 9. The method ofclaim 8 wherein the anchoring element includes a tissue anchor, aflexible connecting element connected to the tissue anchor, and alocking element disposed on the connecting element, and whereininserting the portion of the anchoring element through the overlappedends of the anchoring strap includes: inserting a distal end of adelivery tool through the overlapped ends of the anchoring strap andinto the anatomical feature; ejecting the tissue anchor from thedelivery tool and into the anatomical feature; withdrawing the distalend of the delivery tool from the anatomical feature and the overlappedends of the anchoring strap; and deploying the locking element against aside of the anchoring strap opposite the anatomical feature so as totighten the connecting element and secure the anchoring strap to theanatomical feature.
 10. The method of claim 6 wherein positioning theanchoring strap against the implantable medical device includespositioning a first end of the anchoring strap against the anatomicalfeature at a first location and positioning a second end of theanchoring strap against the anatomical feature at a second location, theimplantable medical device being positioned between the first and secondlocations such that the anchoring strap spans across and over theimplantable medical device.
 11. The method of claim 10 wherein securingthe anchoring strap to the anatomical feature includes securing thefirst end of the anchoring strap to the anatomical feature using a firstanchoring element, and securing the second end of the anchoring strap tothe anatomical feature using a second anchoring element.
 12. The methodof claim 11 wherein securing the first end of the anchoring strap to theanatomical feature includes inserting a portion of the first anchoringelement through the first end of the anchoring strap and into theanatomical feature, and securing the second end of the anchoring strapto the anatomical feature includes inserting a portion of the secondanchoring element through the second end of the anchoring strap and intothe anatomical feature.
 13. The method of claim 12 wherein the first andsecond anchoring elements each include a tissue anchor, a flexibleconnecting element connected to the tissue anchor, and a locking elementdisposed on the connecting element, and wherein: inserting the portionof the first anchoring element through the first end of the anchoringstrap includes: inserting a distal end of a first delivery tool throughthe first end of the anchoring strap and into the anatomical feature;ejecting the tissue anchor of the first anchoring element from the firstdelivery tool and into the anatomical feature; withdrawing the distalend of the first delivery tool from the anatomical feature and the firstend of the anchoring strap; and deploying the locking element of thefirst anchoring element against a side of the first end of the anchoringstrap opposite the anatomical feature so as to tighten the connectingelement of the first anchoring element and secure the first end of theanchoring strap to the anatomical feature; and wherein: inserting theportion of the second anchoring element through the second end of theanchoring strap includes: inserting a distal end of a second deliverytool through the second end of the anchoring strap and into theanatomical feature; ejecting the tissue anchor of the second anchoringelement from the second delivery tool and into the anatomical feature;withdrawing the distal end of the second delivery tool from theanatomical feature and the second end of the anchoring strap; anddeploying the locking element of the second anchoring element against aside of the second end of the anchoring strap opposite the anatomicalfeature so as to tighten the connecting element of the second anchoringelement and secure the second end of the anchoring strap to theanatomical feature.
 14. The method of claim 6 wherein the anchoringelement includes first and second tissue anchors and a flexibleconnecting element therebetween, and wherein the anchoring strapincludes opposite first and second ends and the connecting element iscoupled to and extends along the anchoring strap between the first andsecond ends, and wherein the first tissue anchor is positioned inproximity to the first end and the second tissue anchor is positioned inproximity to the second end.
 15. The method of claim 14 wherein theanchoring strap and the anchoring element are pre-assembled andreleasably coupled to a delivery tool prior to deployment, the deliverytool including a needle cannula and an open distal end, wherein prior todeployment the first and second tissue anchors are positioned seriallywithin the needle cannula and the anchoring strap and at least a portionof the connecting element is positioned external to the needle cannula.16. The method of claim 15 wherein positioning the anchoring strapagainst the implantable medical device includes positioning the firstend of the anchoring strap against the anatomical feature at a firstlocation and positioning the second end of the anchoring strap againstthe anatomical feature at a second location, the implantable medicaldevice being positioned between the first and second locations such thatthe anchoring strap spans across and over the implantable medicaldevice.
 17. The method of claim 15 wherein positioning the anchoringstrap against the implantable medical device and securing the anchoringstrap to the anatomical feature includes: inserting the open distal endof the delivery tool into the anatomical feature at a first location;ejecting the first tissue anchor from the open distal end and into theanatomical feature; withdrawing the open distal end of the delivery toolfrom the anatomical feature; inserting the open distal end of thedelivery tool into the anatomical feature at a second location, theimplantable medical device being positioned between the first and secondlocations such that the anchoring strap spans across and over theimplantable medical device; ejecting the second tissue anchor from theopen distal end and into the anatomical feature; withdrawing the opendistal end of the delivery tool from the anatomical feature; andtightening the connecting element to secure the implantable medicaldevice between the anatomical feature and the anchoring strap.
 18. Amethod of securing an implantable medical device to or adjacent to ananatomical feature in a patient, the method comprising: providing atissue fixation device releasably coupled to a delivery tool, the tissuefixation device including a flexible, adjustable suture assembly, thedelivery tool including first and second needle elements each having atissue-piercing tip; positioning the implantable medical device inproximity to the anatomical feature; inserting the tissue piercing tipsof the first and second needle elements into the anatomical featureproximate the implantable medical device; deploying a portion of thetissue fixation device into the anatomical feature; withdrawing thetissue-piercing tips of the needle elements from the anatomical feature;and tightening the adjustable suture assembly to secure the implantablemedical device to the anatomical feature.
 19. The method of claim 18wherein the tissue fixation device further includes first and secondtissue anchors coupled to the flexible, adjustable suture assembly, andwherein the first and second tissue anchors are coupled to the first andsecond needle elements, respectively, and wherein deploying the portionof the tissue fixation device into the anatomical feature includesdeploying the first and second tissue anchors and a portion of theadjustable suture assembly into the anatomical feature.
 20. The methodof claim 19 wherein the adjustable suture assembly includes a firstsuture loop coupled to the first tissue anchor and a second suture loopcoupled to the second tissue anchor, and wherein tightening theadjustable suture assembly to secure the implantable medical device tothe anatomical feature is performed with the implantable medical devicepositioned within the first and second suture loops, and whereintightening the adjustable suture assembly further includes tighteningthe first suture loop and tightening the second suture loop.
 21. Themethod of claim 19 wherein: inserting the tissue piercing tips includes:inserting the tissue piercing tip of the first needle element into theanatomical feature on a first side of the implantable medical device;and inserting the second tissue piercing tip of the second needleelement into the anatomical feature on a second side of the implantablemedical device such that a portion of the suture assembly spans acrossthe implantable medical device, and wherein tightening the adjustablesuture assembly includes tightening the suture assembly to secure theimplantable medical device against the anatomical feature.
 22. Themethod of claim 21 wherein the first and second needle elements arefixed relative to each other and the handle, and wherein inserting thefirst and second tissue piercing tips includes simultaneously insertingthe first and second tissue piercing tips into the anatomical feature.23. The method of claim 21 wherein the first and second needle elementsare individually actuatable, and wherein inserting the first and secondtissue piercing tips and deploying the first and second tissue anchorsincludes first inserting the first tissue piercing tip into theanatomical feature at the first location and deploying the first tissueanchor, and subsequently inserting the second tissue piercing tip intothe anatomical feature at the second location and deploying the secondtissue anchor.
 24. The method of claim 18 wherein the first needleelement is a first needle cannula having a first side opening, andwherein the second needle element is a second needle cannula having asecond side opening located at a position distal to the first sideopening, and wherein the adjustable suture assembly includes a pre-tiedloop for forming a locking element disposed about the first and secondneedle cannulas prior to deployment of the tissue fixation device. 25.The method of claim 24 wherein the delivery tool further includes anexchange mandrel having a pre-shaped distal end portion slidablydisposed in the first needle cannula, and wherein providing the tissuefixation device releasably coupled to the delivery tool includesproviding a portion of the adjustable suture assembly disposed along thefirst needle cannula and coupled to the distal end portion of theexchange mandrel within the first side opening, and wherein deployingthe portion of the tissue fixation device into the anatomical featureincludes advancing the distal end portion of the exchange mandrel outthe first side opening to the second side opening and engaging thesecond needle cannula with a passing element on a distal end of theportion of the adjustable suture assembly.
 26. The method of claim 25wherein withdrawing the tissue piercing tips includes passing the distalend of the portion of the adjustable needle assembly through thepre-tied loop thereby forming the locking element.